The echo_*() and cat_*() functions in bin/tests/system/conf.sh.common
call the "read" builtin command without specifying the field separator
to use. This results in leading whitespace getting stripped from each
line of the texts passed to those functions, which mangles e.g. pytest
output, hindering test failure troubleshooting.
Address by setting IFS to an empty value for the "read" calls used in
the aforementioned helper functions.
(cherry picked from commit fb87022115)
17fbf25676